NGC 869 and NGC 884 - The Double Cluster (h Chi Persei)
NGC 6729 is a prominent reflection and emission nebula located in the southern constellation Corona Australis, approximately 424 light-years from Earth. This nebula is part of a larger star-forming region, often referred to as the Corona Australis Molecular Cloud complex, which includes other notable objects such as NGC 6726, NGC 6727, and the globular cluster NGC 6723.
NGC 6729 exhibits a complex structure characterized by bright, fan-shaped nebulosity extending from the young variable star R Coronae Australis (R CrA). This star, an intermediate-mass pre-main-sequence object, is a significant source of illumination for the surrounding dust and gas. The nebula's light is primarily due to reflection off dust particles, although there are regions of emission nebulae where ionized gas glows due to ultraviolet radiation from nearby young stars.
The region around NGC 6729 is a fertile site for star formation. Observations in infrared and submillimeter wavelengths reveal numerous young stellar objects (YSOs) and protostars embedded within the dense molecular cloud. The interaction of these forming stars with their natal environment creates a dynamic scene of shock fronts, outflows, and jets, which are often observed as Herbig-Haro (HH) objects. HH objects are formed when jets of material expelled from young stars collide with the surrounding interstellar medium, heating it and causing it to glow.
Photographed from Bamberg and Heidelberg, Germany under Bortle 5 conditions.